Bumper and screen plate combination for rotary hammer mills



Feb. 27, 1951 J. HARRENSTEIN I 2,543,164

BUMPER AND SCREEN PLATE COMBINATION FOR ROTARY HAMMER MILLS Filed June8, 1948 3 SheetsSheet 1 z 14 33: 7 J6 F I r 3 3 IN VEN TOR.

Feb. 27, 31951 J. HARRENSTEIN 2,543,164

BUMPER AND SCREEN PLATE COMBINATION FOR ROTARY HAMMER MILLS Filed June8, 1948 5 Sheets-Sheet 2 Feb. 27, 1951 J. HARRENSTEIN 2,543,164

BUMPER AND SCREEN PLATE COMBINATION FOR ROTARY HAMMER MILLS Filed June8, 1948 3 Sheets-Sheet 3 Patented Feb. 27, 1951 BUMPER AND SCREEN PLATECOMBINATION FOR ROTARY HAMMER MILLS J acob Harrenstein, Forreston, Ill.

Application June 8, 1948, Serial No. 31,707

My invention relates to rotary hammer mills, and more particularly to acombined bumper and screen plate for use therewith, whereby to achieve amore rapid and more efficient grinding of grain or the like.

An object of my invention is to provide a combined bumper and screenplate for rotary hammer mills.

A further object is to provide a combined bumper and screen plate forrotary hammer mills which includes a screen portion intermediate a pairof bumper portions for agitating grain on both sides of the screenportion.

A further object is to provide a combined bumper and screen plate forrotary hammer mills, together with novel means for mounting the same ina mill.

Other objects and advantages reside in the particular structure of theinvention, combination and arrangement of the several parts thereof, andwill be readily understood by those skilled in the art upon reference tothe attached drawing in connection with the following specification,wherein the invention is shown, described and claimed.

In the drawing:

Figure l is a rear elevational View of a rotary hammer mill embodyingthe invention;

Figure 2 is a transverse vertical sectional view through the mill;

Figure B is a horizontal sectional view taken substantially on the planeof the line 3-3 of Figure 2 Figure 4 is a transverse Vertical sectionalview through a combined bumper and screen plate according to theinvention;

Figure 5 is a plan view thereof;

Figure 6 is a perspective view of a separate bumper-plate according tothe invention.

Figure 7 is a sectional view taken along the line 1! of Figure 2 withthe bumper plate removed.

Figure 8 is'a sectional view taken along'the line 8+8 of Figure '2, withparts broken away and with the combined bumper and screenplate removed.

Referring specifically to the drawing, wherein like reference charactershave been used throughout the several views to designate like parts, It]designates generally a hollow base section for a hammer mill whichmounts a discharge trough H for ground grainor the like which receivessuch grindings from the superjacent mill. Ground grain is dischargedfrom the trough H by means of a screw conveyor or 3 Claims. (Cl.241--88) the like l2. An upper or cover section I3 for the base I0 ishinged thereto by any suitable hinges I4, and mounts an inlet spout 15through which unground grain is fed to the mill. The side walls of thecover and base sections I0 and l 3 have mounted therebetween a shaft I"!mounting a plurality of radially-directed beater arms l8 having hammersis formed on the ends thereof. As so far described, the mill accordingto the invention is conventional and forms no part of my invention. 7

Any suitable means, such as the motor 20, is utilized to drive the shaftll, whereby to rotate the beater arms l8 and their associated hammersH3. The motor 2|] may be mounted on any suitable bracket 2| outwardly ofone side of the mill.

The base portion ll) of the mill is provided with a floor 24 for themill which is in the form of a semi-cylinder, the semi-cylinder floorbeing formed with a discharge opening 25 for the discharge of groundgrain or the like into the discharge trough II. The opening 25 extendsinwardly of and is spaced from one of the side and both of the end edgesof the semi-cylinder 24 and terminates at a point substantially midwayof the semi-cylinder. Each of the end edges of the semi-cylinder isprovided with embracing means which face each other, such means takingthe form of an inwardly directed flange 26 which is spaced from theadjacent portion of the semi-cylinder 24 and forms therewith a groove. Acombined bumper and screen plate 21 conformably shaped to fit within thefio'or 24 or in the form of a semi cylinder is insertable between thefacing grooves and is pushed inwardly until the plate is completelysuperposed upon the semicylinder 24. The plate 21 comprises animperforate quarter segment of a cylinder 28 having a plurality ofspaced protuberances or rounded bumpers 3D projecting from a facethereof and a perforated or screen quarter segment of a cylinder 29arranged in side by side relation with respect to imperforate segment 28and secured thereto. The plate '21 is positioned with respect to thesemi-cylinder 24 so that the imperforate segment 28 with its bumpers 30facing outwardly overlies and abuts the adjacent portion of the cylinder24 and the screen or perforated segment 29 overlies the dischargeopening 25 and abuts the adjacent bounding side and end portions of thesemi-cylinder floor 24. It is to be noted that the plate 21 is appliedto the semi-cylinder floor 24, after the cover I3 has been raised, byinserting the free end 34 into the grooves at the right 3 hand side ofthe mill, Figure 2. The plate 21 is then slid around until the leadingedge 34 encounters any suitable stops 33 formed on the flanges 26.

There is no particular need to fasten the plate 21 in place, as will beapparent hereinafter.

Referring now to Figure 2 and to Figure 6, that portion 42 of the coverl3 between the inlet opening l6 and the free edge 40 of the cover I3 islikewise provided with embracing means facing each other, said meansembodying inwardly directed flanges 4!, Figure '7, which are concentricto the portion 42 and provide therebetween a pair of opposed grooves. Abumper plate 35, Figure 6, which is of the same configuration as theportion 42 or in the form of a segment of a cylinder insertable betweenthe opposed grooves formed by the flanges 4!. The bumper plate 35 ispreferably of double thickness and comprises a pair of plates 36 and 31arranged in superposed abutting relation with respect to each other andsecured together. As shown in Figure 6 a plate 31 is in the form of asegment of a cylinder and has one of its end edges turned inwardly toform a shoulder 39, the shoulder being spaced from the adjacent portionof the plate to provide a groove. Positioned in superposed abuttingrelation with respect to the plate 31 and having one end extending intothe groove formed by the shoulder 39 and the adjacent portion of theplate 3'! is a plate 36. With the cover [3 raised the plate 35 isinserted therein from the end thereof adjacent the free edge 40. Thismovement is continued until the shoulder 39 of the inwardly turned endedge 38 abuts the ends of the flanges 4I- and prevents further movement.At this time the opposite ends 43 of the plates 36 and 3'! aresubstantially flush with the inlet opening Hi. It will be noted thatwhen the cover I3 is closed, the double thickness, or rather triplethickness, of the lower end of the bumper plate 35 overlies the ends ofthe grooves provided by the lower flanges 26 and prevents slidingmovement of the lower plate 2'! in such grooves. Inasmuch as the stops33 limit movement of the plate 21 in the opposite direction, the plates21 and 35 are securely positioned in place without the use of bolts orscrews. The bumper plate 35 is likewise provided with a plurality oftransversely-extending protuberances or bumpers 45 which aresubstantially similar to the bumpers 30 of the plate 21. It is apparent,thus, that the trailing edge 44 of the plate 21 not only is preventedfrom escaping from its groove by engagement with the lower end of thebumper plate 35, but the latter is likewise prevented from escaping fromits grooves by its engagement with the trailing edge 44 of the plate 21.

Thus, it is apparent that I have provided novel means for securing theplates in place without the use of bolts, screws or the like. At thesame time, by providing the particular plates of the invention, thegrain fed to the mill through the spout I5 and inlet opening I6 isagitated or held back by the bumpers 30 and 45, so that the hammers l9have a better chance to hit the grain. That is to say, the grain bouncesoff of the bumpers and is thrown into the path of the hammers l9 toinsure better pulverization of the grain. When the grain is sufficientlypulverized, it escapes into the discharge trough H through theperforations 3| in the screen sec- 4 4 invention, it is to be understoodthat the same is susceptible of other forms and expressions.Consequently, I do not limit myself to the precise structure shown anddescribed hereinabove except as hereinafter claimed.

I claim:

1. In a rotary hammer mill including a semicylinder floor, said floorbeing provided with a discharge opening extending inwardly of and spacedfrom one side and both end edges of and terminating at a pointsubstantially midway of said semi-cylinder floor for the discharge ofgrain therethrough, embracing means engaging each of the end edges ofsaid semi-cylinder floor and facing each other, and a combined bumperand screen plate conformably shaped to fit within said semi-cylinderfloor insertable between the facing embracing means and superposed uponsaid floor, said plate embodying a pair of segments arranged in side byside relation and secured together, one of said segments being providedwith a perforated screen and the other of said segments beingimperforate and having one face provided with a plurality of spacedprotuberances projecting therefrom, the screen segment overlying saiddischarge opening with the imperforate segment overlying the adjacentportion of said floor.

2. In a rotary hammer mill including a semi cylinder floor, said floorbeing provided with a discharge opening extending inwardly of and spacedfrom one side and both end edges of and terminating at a pointsubstantially midway of said semi-cylinder floor for the discharge ofgrain therethrough, an inwardly directed flange engaging each of the endedges of said semicylinder floor and spaced from the adjacent portionsthereof to thereby form a groove, the grooves facing each other, and acombined bumper and screen plate comformably shaped to fit within saidsemi-cylinder floor insertable between the facing grooves and superposedupon said floor, said plate embodying a pair of segments arranged inside by side relation and secured together, one of said segments beingprovided with a perforated screen and the other of said segments beingimperforate and having one face provided with a plurality of spacedprotuberances projecting therefrom, the screen segment overlying saiddischarge opening with the imperforate segment overlying the adjacentportion of said floor.

3. In a rotary hammer mill including a semicylinder floor, asemi-cylinder cover superposed upon said floor and connected to thelatter along one of its side edges for opening and closing movement withrespect thereto, said cover being subdivided into two portions with oneportion having embracing means engaging each of the end edges and facingeach other, said floor being provided with a discharge opening extendinginwardly of and spaced from one side and both end edges of andterminating at a point substantially midway of said semi-cylinder floorfor the discharge of grain therethrough, embracing means engaging eachof the end edges of said semi-cylinder floor and facing each other, acombined bumper and screen plate conformably shaped to fit within saidsemi-cylinder floor insertable between the facing embracing means andsuperposed upon said floor, said plate embodying a pair of segmentsarranged in side by side relation and secured together, one of saidsegments being provided with a perforated screen and the other of saidsegments being REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date 978,034 Kinsey Dec. 6, 1910991,477 Buchanan May 9, 1911 1,354,855 Simpson Oct. 5, 1920 1,420,354Williams June 20, 1922 1,606,692 Brooks Nov. 9, 1926 2,066,621 Gray Jan.5, 1937 2,215,226 Meyer Sept. 17, 1940 2,385,767 Wagner Sept. 25, 1945

